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Increasing demand of shea products (kernels and butter) has led to the assessment of the state-of-the-art of these products. In this review, attention has been focused on macronutrients and micronutrients of pulp, kernels, and butter of shea tree and also the physicochemical properties of shea butter. Surveying the literature revealed that the pulp is rich in vitamin C (196.1 mg/100 g); consumption of 50 g covers 332% and 98% of the recommended daily intake (RDI) of children (4-8 years old) and pregnant women, respectively. The kernels contain a high level of fat (17.4-59.1 g/100 g dry weight). Fat extraction is mainly done by traditional methods that involve roasting and pressing of the kernels, churning the obtained liquid with water, boiling, sieving, and cooling. The fat (butter) is used in food preparation and medicinal and cosmetics industries. Its biochemical properties indicate some antioxidant and anti-inflammatory activities. Large variations are observed in the reported values for the composition of shea products. Recommendations for future research are presented to improve the quality and the shelf-life of the butter. In addition, more attention should be given to the accuracy and precision in experimental analyses to obtain more reliable information about biological variation.

The synthesis of human milk fat substitutes (HMFS) which show a high degree of similarity to human milk fat (HFM) is of great interest to ensure a supply in infant nutrition with a triacylglyceride composition as close as possible to mothers milk. Biocatalyzed modifications of natural oils using microbial or plant-derived enzymes enable the production of high-value HMFS. Due to the mild reaction conditions and the exceptionally high sn-1,3-regioselectivity of these enzymes, they are preferred over chemical catalysis in the development of these lipids with desired nutritional and functional properties. In this article, research spanning over 20 years of lipase-catalysis for the production HMFS is reviewed. Specific attention is paid to the evaluation of the regiospecificity of the biocatalysts, choice of natural oils and acyl donors, production processes, purification of the HMFS, and analytical procedures for their characterization. (Résumé d'auteur

Pentadesma butter (Pentadesma butyracea, sabine, clusiaceae) is an extract of the kernels of tree fruits in West Africa and similar to shea butter. The study of the fatty acid composition, triacylglycerols, sterols and tocopherols of Pentadesma butter was carried out on seeds collected in ten production areas in Benin. The results obtained show that the composition in fatty acids is characterized by the presence of stearic acid and oleic acid, which represent nearly 96% of the total fatty acids. The triacylglycerols profile of the different butters is marked by the overwhelming presence of the triacylglycerols SOS and SOO. The unsaponifiable fraction shows, for the sterolic composition, a predominance of stigmasterol (nearly 68% of the total sterols) whilst the b-tocopherol is the main tocopherol.

Structured triacylglycerides with medium-chain fatty acids (caprylic acid) in sn1-and sn3-positions and a longchain unsaturated fatty acid (oleic or linoleic acid) in the sn2-position of glycerol (MLM) were synthesized by lipase catalysis in a two-step process. First, pure 2-monoacylglycerides (2-MG) were synthesized by alcoholysis of triacylglycerides (triolein, trilinolein, or peanut oil) in organic solvents with 1,3-regiospecific lipases (from Rhizomucor miehei, Rhizopus delemar, and Rhizopus javanicus). The 2-MG were purified by crystallization and obtained in up to 71.8% yield. These 2-MG were esterified in a second reaction with caprylic acid in n-hexane to form almost pure MLM. For 2-MG obtained from peanut oil, the final product contained more than 90% caprylic acid in the sn1-and sn3-positions, whereas the sn2-position was composed of 98.5% unsaturated long-chain fatty acids. Reaction conditions for both steps were optimized with respect to source and immobilization of lipase, water activity, and solvent. JAOCS 75, 703-710 (1998).

1,3‐Oleoyl‐2‐palmitoylglycerol (OPO), an important structured triglyceride in infant nutrition, was synthesized by a two‐step process in high yields and purity using sn1,3‐regiospecific lipases. In the first step, tripalmitin (TP) was subjected to an alcoholysis reaction in an organic solvent catalyzed by sn1,3‐regiospecific lipases yielding the corresponding 2‐monopalmitin (2‐MP). The 2‐MP was isolated in up to 85% yield and >95% purity by crystallization and esterified in the second step with oleic acid using the same lipases to form the structured triglyceride OPO in up to 78% yield containing 96% palmitic acid in the sn2‐position. Water activity, solvent, as well as carrier for lipase immobilization strongly influenced the yield and purity of products in both steps. The best results were achieved with lipases from Rhizomucor miehei and Rhizopus delemar immobilized on EP 100 and equilibrated to a water activity of 0.43. Special emphasis was given to develop this process in solvents that are allowed to be used in foodstuffs and to perform the second step in a solvent‐free system. © 1999 John Wiley & Sons, Inc. Biotechnol Bioeng 64: 678–684, 1999.

Keywords: Branched chain amino acid; protein; leucine; isoleucine; valine * BCAA -branched chain amino acids; CPcrude protein; Leu -leucine; Ileisoleucine; Valvaline 1 Brestenský et al., (2013), 2 NRC (2012), 3 Gottlob et al., (2012)Branched chain amino acids (BCAA) -leucine, isoleucine and valine are essential amino acids which are metabolized directly in muscles and offer energy fuel to performance of the work. There is lot of evidences supporting the positive effect of BCAA supplementation on muscle growth. The main importance is attached particularly to leucine. There was observed that leucine supplementation increased protein synthesis in skeletal muscles after resistance exercise in young people and in elderly people suffered by sarcopenia as well. There is not exactly clear, what is the reason for the positive effect of BCAA to increase protein synthesis in muscles. Besides the positive effect of BCAA on muscle growth, there was observed their positive effect against fatigue and on a production of endogenous glucose, which is necessary to maintain the glucose balance in body during adaptation to stress. The minimum and maximum dose of BCAA is not established, but the daily recommended amount of leucine : isoleucine : valine is in a ratio 40:20:20 mg.kg body weight -1 . It is recommended to use the mixture of BCAA rather than leucine individual, because of depletion other BCAA in body. There was observed no toxicity of BCAA even at high doses. The present review describes the metabolism of action and effect of BCAA on protein synthesis and physiological functions in human. ARTICLE INFO

Structured triglycerides of the ABA-type, containing one type of fatty acid (A) in the sn-1 and sn-3 positions and a second type of fatty acid (B) in the sn-2 position of the glycerol, were synthesized using lipases. The highest yields and purities were achieved in a two-step process, where a triglyceride of the B-type was subjected to an alcoholysis reaction in an organic solvent catalyzed by sn-1,3-regiospecific lipases yielding the corresponding 2-monoglyceride (2-MG). Using this strategy, e.g., 2-monopalmitin (2-MP) was obtained in up to 88% yield at >95% purity by crystallization. Esterification of 2-MP with oleic acid resulted in the formation of 1,3-oleyl-2-palmitoylglycerol in up to 72% yield containing 94% palmitic acid in the sn-2 position. The best lipases were from Rhizomucor miehei, Rhizopus delemar, and Rhizopus javanicus. Water activity, solvent, and carrier for lipase immobilization strongly influenced the yield and purity of the products in both steps. Futhermore, 2-MG from fish oil were produced by alcoholysis in up to 84% yield at >95% purity. JAOCS 75, 1527-1531 (1998). FIG. 3. Time course of the formation of 1,3-oleyl-2-palmitoyl-glycerol (OPO) from 2-MP with oleic acid in n-hexane with Lipozyme. For abbreviations, see Figure 1.